The practice of astrology recognizes four cardinal signs of the zodiac: Aries, Cancer, Libra, and Capricorn — sometimes called reacting signs. It associates those people born "under" one of these with certain human behaviors and traits like being active, self-motivated, insightful and ambitious.
The word "cardinal" originates from the Latin word for "important," since they each mark the turning point of a temperate season. They were called moveable by traditional astrologers because, as Bonatti says, the "air" changes when the Sun enters each of these signs, bringing a change of season. Sometimes the word cardinal is confused with the word angular. Angular signs are those signs which are located on the astrological angles of any given natal chart. Angular houses may be cardinal, fixed or mutable, depending on the birth time of the chart, but only Aries, Cancer, Libra, and Capricorn are cardinal signs. Their starts are related to equinoxes and solstices.
The four cardinal signs of the zodiac are:
- Aries (): the Sun's passage through which begins the spring in the northern hemisphere, and autumn in the southern hemisphere.
- Cancer (): which begins the summer in the northern hemisphere, and winter in the southern hemisphere.
- Libra (): which begins the autumn in the northern hemisphere, and spring in the southern hemisphere.
- Capricorn (): which begins the winter in the northern hemisphere, and summer in the southern hemisphere.
- Guido Bonatti, Liber Astronomiae, Part II. [tr. Robert Zoller]. Project Hindsight Latin Track, The Golden Hind Press (Berkeley Springs, WV, 1994.) Pp. 2-3.